<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<!-- 同步脚本，按顺序加载执行，会阻塞页面渲染 -->
<!-- <script src="./a.js"></script>
<script src="./b.js"></script>
<script src="./c.js"></script> -->

<!-- 异步脚本，异步加载脚本，不阻塞页面渲染 -->
<!-- 设置了 type="module" 的脚本为异步脚本，异步加载，DOM加载完成后执行 -->
<!-- <script type="module" src="./a.js"></script>
<script src="./b.js"></script>
<script src="./c.js"></script> -->

<!-- 
    defer 异步加载脚本，DOM加载完成后执行  DOMContentLoaded
    async 异步加载脚本，加载完成后立即执行
 -->
<!-- <script defer src="./a.js"></script>
<script src="./b.js"></script>
<script src="./c.js"></script> -->

<!-- <script async src="./a.js"></script>
<script src="./b.js"></script>
<script src="./c.js"></script> -->

</head>
<body>
    
<div class="wrap">
    <div class="box">box</div>
    <div class="box">box</div>
    <div class="box">box</div>
    <div class="box">box</div>
    <div class="box">box</div>
</div>

</body>
</html>